The purpose of this project is to determine the incidence rates, rates of progression, and risk factors for the chronic complications of NIDDM. The study is conducted in the Pima Indians of the Gila River Indian Community, who have participated in a longitudinal epidemiologic study since 1965 (see project Z01 DK 69000). Risk factors for the major complications of diabetes, retinopathy, nephropathy, and coronary artery disease, are determined by longitudinal follow-up of diabetic subjects. Methods of ascertainment of these complications include fundus photography, measurement of urine albumin and serum creatinine concentrations, and electrocardiography. The common I/D polymorphism in the angiotensin-1-converting enzyme (ACE) has been associted with coronary artery disease (CAD). Because the D allele, which is associated CAD in other populations, is less common in Pima Indians, this gene might account for the lower incidence of CAD among Pimas. Among Pimas, the ACE I/D genotype was related to plasma glucose and serum lipids, but not with CAD. There was also no significant relationship of the ACE I/D genotype with microvascular disease, although both nephropathy and retinopathy were less frequent in diabetic subjects with the DD genotype, in contrast to some previous reports. Thus this genotype does not appear to be an important risk factor for CAD or microvascular disease among Pimas. Studies of the genetic basis of diabetic nephropathy are described in project report #Z01 DK 69028-10 PECR.